1. Field of the Invention
The present invention relates to a vehicle that includes a main frame constituted by a structure in which an outer member and an inner member are connected to each other and that uses reinforced plastics in a part of a panel constituting the frame of the vehicle.
2. Description of the Related Art
Conventionally, in a vehicle including a main frame constituted by a structure in which an outer member and an inner member are connected to each other, the outer and inner members that constitute the main frame of the vehicle are made of a steel sheet (a high-tensile steel sheet or a super-high-tensile steel sheet), an iron sheet, an aluminum sheet, or the like. Sufficient strength has been required for such a vehicle having a main frame constituted by a structure in which outer and inner members are connected to each other in order to ensure safety of a vehicle cabin in the case of a sudden front or side shock or an offset collision.
However, if strength is increased, the continuity of the characteristics of load transmission to a vehicle when executing a turn on a curve will be compromised. This will influence vehicle stability. Accordingly, a balance between collision safety and vehicle stability has been required.
For example, Japanese Unexamined Patent Application Publication (JP-A) No. 2000-108930 discloses a lower structure of a vehicle side that disperses and transmits a collision load from a front or side of a vehicle to other members and suppresses deformation due to a collision.
JP-A No. 2001-71948 discloses a structure that is provided on a side roof of a vehicle side with a rail reinforcing member and on a side seal with a seal strength adjusting member, respectively, and that changes the vehicle deformation mode upon the occurrence of a side collision.
On the other hand, JP-A No. 2004-123036 discloses a technique for molding at least one of an inner panel and an outer panel out of fiber reinforced plastics in a structure for fixing a wire harness to a vehicle body.
However, in the above three Japanese Unexamined Patent Application Publications, the vehicle frame has insufficient strength and stiffness in view of vehicle stability and collision safety.